Flame hardening device



March 3, 1942.

G. O. GRIDLEY FLAME HARDENING DEVICE Filed Feb. 6, 1940 INVENTOR GEORGE 0. G/ZIOLE Y ATTORNEYS Patented Mar. 3, 1942 UNITED STATE S PATENT OFFlCE. I

FLAME HARDENING DEVICE George 6. Gridley, Berlin, com, assignor-to The New Britain Machine Gompany, New Britain,

Conn., acorporation of Connecticut 1 Application February 6, 1940, Serial No. 317,474 1 Claim. 01. 266-4) My invention relates to a hardening device hardened and upon movement the heated Sllr-" face is quenched by the water sprays emanating from the flam hardening head.

It is an object of the invention to provide an improved, simple, easily controlled, flame hardening device, particularly adapted for surface hardening generally cylindrical objects such as shafts, stems and the like. 1'

Another object is to provide a hardening device of the character indicated, which is simple 'and economical in construction and operation, and

Y which" will operate for hardening with great rapidity.

Anotherobject is to provide an improved flame hardening head.

Other objects and various features of novelty and invention will be hereinafter pointed out or will become apparent to those skilled in the art.

Briefly stated, I provide in a preferred form of the invention a hardening head comprising a head plate having therein a transversely extending gas distribution chamber, a row of flame openings communicating with and extending from said gas distribution chamber to the outside of said head plate, a cooling water chamber extending along and generally parallel to said gas distribution chamber but separated therefrom by a relatively thin wall and quenching water, outlets in proximity to said flame openings and extending from said cooling water chamber to the outside of the head plate. The hardening head may also include a gas inlet communieating with said gas distributing chamber and a water conduit surrounding a part of such gas inlet connection and communicating with sai cooling water chamber.

In the drawing which shows, for illustrative purposes only, a preferred form of the invention,

t each other for progressively heating and immedi- Fig. 2 is a right-handend view in elevation .of the hardening head shown in Fig. 1;

Fig. 3 is a left-hand or inside end elevation partly in section of the head plate shown in Figs. 1 and 2.

,The invention as illustrated is embodied in a hardening head for surface hardening a generally cylindrical piece such as a shaft or stem, or

I other object. The shaft or other work piece is moved relatively to the hardening head as by revolving it, and simultaneously the work piece and hardening head are traversed relatively to ately quenching the surface.

Various flame hardening. heads may be employed but I have devised an improved form having substantial advantages, particularly in the matter of simplicity, and ,in the ability to keep the gas cool and prevent flash-backs; My improved flame hardening head is illustrated in Figs. .1, 2 and 3. The head may comprise a main casing or tube 60 closed at the forward end by what I term a head plate 6| of the'proper outside contour. The head plate 6| may-be secured to the tube 60 as by brazing at the joint between the two. The head plate 6i is provided with gas outlet openings which. I will refer to as flame openings 62 extending across the head. Within the head plate 6| thereis a distributing chamber 63 with which the flame openings 62 communicate. Preferably the head plate is provided with a second distributing chamber 64, communicat-.

chambers 6463 and be evenly distributed to the various flame openings 62. The water inlet pipe 63 enters the casing near the rear and the entire head exteriorly of the tube 66 contains water'in'the entire annular space thereof. Thus the gas in the pipes 6666 will be kept cool. Furthermore, the flame head 'is preferably provided with a water chamber 16 extending across the head in close proximity .to the distributing chambers 63-44 and is separated therefrom by a very thin wall so that water in the water chamber it will serve to continuously maintain the gas in the distributing chambers cool and flashbacks will be reduced to a minimum. The water outlets II from the head plate preferably extend into the water chamber it so that a fresh supply of cool water will be constantly supplied to'th'at water chamber and constantly maintain the gas chambers cool.

In operation the gas is lighted at the row of flame openings and water is turned on to enter the cooling water chamber ll so that water may pass from the cooling water chamber through the quenching water outlets to the outside of the head plate. The speed or movement as produced by the operator must be fast enough to prevent burning of the object being treated and yet must be slow enough to permit the surface 0! the object to be heated to the requisite temperature before the heated part is quenched by the water sprays.

While the invention has been described in considerable detail and a preferred form illustrated, it is to be understood that various changes and modifications may be made within the scope of the invention as defined in the appended claim.

I claim:

In a hardening head, a head plate having a transversely extending gas distribution chamber therein, said head having a row 01' flame openings communicating with and extending from said gas distribution chamber to the outside or said head plate. said head plate having a coolins water chamber formed therein and extending along generally parallel to said gas distribution chamber and separated therefrom by a relatively thin wall, said head having quenching water outlets communicating with and extending from said cooling water chamber to the outside of said head plate and located in proximity to said flame openings, a gas inlet connection to said head plate and communicating with saidgas distribution chamber, and a water conduit connected to said head plate and surrounding a part 0! said gas inlet connection and in open communication with said cooling water chamber in said head plate.

GEORGE O. GRIDLEY. 

